Apparatus for printing on plastic disk

Abstract

A printer for printing graphic and alphanumeric information on plastic disks utilizing a printhead having a line array of print pixels. The printhead is pivotally mounted and has an adjustable force mechanism to urge the line array of print pixels into contact with a plastic disk; the plastic disk is mounted on a movable carriage which linearly passes beneath the printhead and the adjustable force mechanism exerts a variable force which is a function of the position of the disk beneath the printhead.

What is claimed is: 
     
       1. An apparatus for printing information on a surface with uniform printhead pressure, comprising: a) a printer frame having a movable carriage mounted thereon, said carriage having means for supporting a printing surface, and said carriage being movable over a linear path of travel;   b) a printhead pivotally mounted over said carriage path of travel, said printhead having a line array of print pixels;   c) means for controllably pivoting said printhead, whereby the upward and downward force on said line array of print pixels may be selectively applied;   d) means for moving said carriage over said linear path of travel, including means for detecting the position of said carriage; and   e) means for utilizing the position detected by said means for detecting to create a force component based on said detected position, and including means for determining the length of the line array of print pixels which is applied to the printing surface for each position of said carriage, and means for transmitting said force component to said means for controllably pivoting, the downward force applied to said line array of pixels being determined by said carriage position and the length of the line array of print pixels applied to said printing surface.   
     
     
       2. The apparatus of claim 1, further comprising a printer ribbon connected between a supply reel and a take-up reel, said printer ribbon passing between said carriage and said printhead. 
     
     
       3. The apparatus of claim 2, further comprising means for controlling said supply reel and take-up reel. 
     
     
       4. The apparatus of claim 3, wherein said carriage means for supporting a printing surface further comprises a resilient surface. 
     
     
       5. The apparatus of claim 4, wherein said line array of print pixels is pivotally connected to a pivot arm, and said pivot arm is connected to receive said force component. 
     
     
       6. An apparatus for printing information on a compact disk surface with uniform printhead pressure, comprising: a) a printer frame having a movable carriage mounted thereon, said carriage having means for supporting a printing surface, and said carriage being movable over a linear path of travel;   b) a printhead pivotally mounted over said carriage path of travel, said printhead having a line array of selectively heatable print pixels;   c) means for controllably pivoting said printhead, whereby the upward and downward force on said line array of print pixels may be selectively applied;   d) means for moving said carriage over said linear path of travel, including means for detecting the position of said carriage; and   e) means for utilizing the position detected by said means for detecting to create a force component based on said detected position, and based upon the length of said line array of print pixels which is applied to said printing surface at each said detected possition, and means for transmitting said force component to said means for controllably pivoting, the downward force applied to said line array of pixels being determined by said carriage position and the force per unit area of print pixels against said compact disk is constant.   
     
     
       7. The apparatus of claim 6, wherein said compact disk futher comprises a recordable compact disk. 
     
     
       8. The apparatus of claim 6, further comprising a printer ribbon connected between a supply reel and a take-up reel, said printer ribbon passing between said carriage and said printhead. 
     
     
       9. The apparatus of claim 8, further comprising means for controlling said supply reel and take-up reel. 
     
     
       10. The apparatus of claim 6, wherein said carriage means for supporting a printing surface further comprises a resilient surface. 
     
     
       11. The apparatus of claim 10, wherein said line array of print pixels is pivotally connected to a pivot arm, and said pivot arm is connected to receive said force component. 
     
     
       12. A printer having a carriage movable over a linear path of travel and a printhead having a line array of selectively heatable print pixels pivotally mounted over said path of travel about an axis parallel to said path of travel, comprising: a) control means for moving said carriage and for detecting the position of said carriage over said path of travel;   b) a printhead driver connected to said control means, said printhead driver having means for controlling the force of said printhead toward said carriage;   c) means for holding an article for printing on said carriage, the force of said printhead being determined by the position of said carriage over said path of travel: and   d) means for calculating the length of said line array of pixels positioned above said article, and for controlling said printhead driver as a result thereof to correspondingly vary the force of said printhead.   
     
     
       13. The apparatus of claim 12, wherein said means for holding an article comprises a resilient surface. 
     
     
       14. The printer of claim 12 further comprising a printer ribbon interposed between said printhead and said carriage. 
     
     
       15. The apparatus of claim 12, wherein said article comprises a plastic disk. 
     
     
       16. The apparatus of claim 15, further comprising a take-up reel connected to said printer ribbon and a ribbon controller connected to said control means, whereby said ribbon is moved at a rate corresponding to movement of said carriage. 
     
     
       17. The apparatus of claim 16, wherein said line array of pixels is mounted as a part of said printhead. 
     
     
       18. A thermal printer having a carriage movable over a linear path of travel and a printhead having a line array of selectively heatable print pixels pivotally mounted over said path of travel about an axis parallel to said path of travel, comprising: a) control means for moving said carriage along said path of travel;   b) a cam lobe affixed to said carriage; said cam lobe having a surface curvature determined by a calculating the length of said line array of print pixels positioned above said article for each position of said carriage;   c) a pivot bar having a cam follower guided by said cam lobe and having a distal end connected to said printhead, the downward force applied against said printhead by said distal end being variable; and   d) means for holding a compact disk for printing on said carriage, the downward force of said printhead being determined by the position of said carriage over said path of travel.   
     
     
       19. The apparatus of claim 18, wherein said article comprises a recordable compact disk. 
     
     
       20. The apparatus of claim 19, wherein said line array of pixels is mounted as a part of said printhead. 
     
     
       21. The apparatus of claim 20, wherein said means for holding a compact disk comprises a resilient surface. 
     
     
       22. A thermal printer comprising: a) a printer housing containing a carriage movable over a linear path of travel, and a selectively heatable line array of print pixels movably positionable in said housing and adjacent said path of travel;   b) an arcuate cam surface affixed to said carriage and movable therewith;   c) a pivot bar pivotally attached to said housing and having a cam roller positioned to contact said arcuate cam surface, said pivot bar having a movable distal end;   d) a pivot arm pivotally attached to said housing about a pivot pin having an axis aligned with said linear path of travel, said pivot arm having a distal end connected to said pivot bar distal end;   e) said line array of print pixels pivotally mounted to said pivot arm; whereby movement of said carriage along said linear path of travel pivotally moves said pivot bar and said pivot arm thereby causing a downward force on said line array of print pixels which is related to the position of said carriage; and.   f) a second cam engageable against said pivot arm and motor means for actuating said second cam to pivotally raise and lower the distal end of said pivot arm.   
     
     
       23. The apparatus of claim 22, wherein said carriage further comprises a resilient surface for supporting a compact disk. 
     
     
       24. The apparatus of claim 23, wherein the connection between said pivot bar and said printhead bracket further comprises a resilient spring. 
     
     
       25. The apparatus of claim 24, wherein said compact disk further comprises a recordable compact disk. 
     
     
       26. A method for printing on circular plastic disks with a line array of thermally activated print pixels, comprising: providing a line array of print pixels; a) supporting the plastic disk on a resilient support base;   b) moving said support base at a uniform rate of speed along a path of travel which is adjacent said line array of print pixels and normal to the alignment of said line array of print pixels;   c) interposing a printing transfer ribbon between said line array and the plastic disk;   d) applying a force on said line array, against said transfer ribbon and the plastic disk, said force being directly proportional to the length of said line array which contacts said transfer medium and the plastic disk; and wherein said plastic disk is circular and has an overall diameter D, and the instantaneous position of said line array relative to an edge of the plastic disk is d', said force further comprises a force which is determined by the equation:   F=DKsin{arccos(1=2d'/D); where k is a constant; and       e) selectively activating said thermally activated print pixels to transfer printed pixels from said transfer medium to the plastic disk.   
     
     
       27. A printer having a carriage movable over a linear path of travel and a printhead movably positionable over said path of travel, comprising: a) a printer housing for receiving said carriage and for holding said printhead;   b) an arcuate cam surface affixed to said carriage and movable therewith;   c) a pivot bar pivotally attached to said housing and having a cam roller positioned to contact said arcuate cam surface, said pivot bar having a movable distal end;   d) a pivot arm pivotally attached to said housing about a pivot pin having an axis aligned with said linear path of travel, said pivot arm having a distal end connected to said pivot bar distal end;   e) said printhead pivotally mounted to said pivot arm; whereby movement of said carriage along said linear path of travel pivotally moves said pivot bar and said pivot arm, thereby causing a downward force on said printhead which is related to the position of said carriage; and   f) a second cam engageable against said pivot arm, and motor means for actuating said second cam to pivotally raise and lower the distal end of said pivot arm.   
     
     
       28. The apparatus of claim 27, wherein the connection between said pivot bar and said pivot arm further comprises a resilient spring. 
     
     
       29. The apparatus of claim 28, wherein said carriage further comprises a resilient surface for holding an article for printing. 
     
     
       30. The apparatus of claim 29, wherein said article further comprises a plastic disk. 
     
     
       31. A method for printing on circular plastic disks with a line array of thermally activated print pixels, comprising: provide a line array of print pixels a) moving the plastic disk at a uniform rate of speed along a path of travel which is adjacent said line array of print pixels;   b) interposing a printing transfer medium between said line array and said plastic disk;   c) applying a force on said line array, against said transfer medium and the plastic disk, said force being directly proportional to the length of said line array which contacts said transfer medium and the plastic disk; and wherein the plastic disk is circular and has an overall diameter D, and the instantaneous position of said line array relative to an edge of said plastic disk is d', said force further comprises a force which is determined by the equation:   F=DKsin{arccos(1-2d'/D); where k is a constant; and       d) selectively activating said thermally activated print pixels to transfer printed pixels from said transfer medium to said plastic disk.   
     
     
       32. The method of claim 31, wherein the step of interposing a transfer medium between said line array and said plastic disk further comprises moving said transfer medium at a uniform rate along a direction parallel to said path of travel. 
     
     
       33. The method of claim 32, wherein said transfer medium further comprises an ink ribbon, and said step of moving said transfer medium further comprises moving said ink ribbon between a supply and take-up reel. 
     
     
       34. The method of claim 31, further comprising the initial , step of supporting said plastic disk on a resilient support surface. 
     
     
       35. The method of claim 34, wherein said plastic disk further comprises a compact disk. 
     
     
       36. The method of claim 34, wherein said plastic disk further comprises a recordable compact disk.